I'm looking towards the future when I have to swap out / replace one of my devices. If I have a device that has multiple smartapps associated with to it, the process of replacing it seems like it could be a bit painful. Having an option on each device page allowing you to "swap" it out with another would make the process painless for the end user.
As we all know, devices die. Have a good process to replace them in the app would benefit everyone!

The iOS team got it in before the mobile teams paused bi-weekly releases for the big app rewrites. Our Android team is the largest mobile development team we have and I’m pretty sure we have more Android users working for SmartThings at this point than iOS.

If you haven’t seen it, this is the difference between the current build on the Play Store and the one we’re almost finished with:

Tyler:

When they're ready! I'm using our internal Android alpha version and it's great. Loading time on every page is near instant.

This is a special Z-Wave feature designed to be infrequently used in the situation where a device disappears, dies, or in any way becomes completely and permanently unresponsive. It allows you to replace the device with another of the same kind of device without going through the entire setup again.

When you attempt to replace a device, the hub will first try to contact the device to determine if it is actually unresponsive. This can take from a couple seconds to tens of seconds depending on several factors that the Z-Wave protocol uses to determine how long is reasonable to wait for a response. When the hub is satisfied that the device is unresponsive, it will initiate the replacement search process. Push the button on the new device or follow whatever the device’s usual procedure is to add it to the network.

Some further info:

The replacement search is like a developmentally stunted version of inclusion. It uses the same mechanism but the API has less feedback and control. From the new device’s point of view, it is just getting included – it doesn’t know that it’s getting a preowned network ID – so it must be in an excluded state and put in learn mode as if it were being included. The device network ID is the only info that links a device in the SmartThings cloud to the actual device on the network, so once the new device is included and given the failed device’s ID, all communication is effectively redirected to it without anything having to change in the cloud.

There are a couple ways this can make a mess. The protocol has no way of preventing you from replacing the device with a totally different kind of device. If you replace a switch with a motion sensor it will just confuse everything. Also, if you trick the hub into thinking the device was unresponsive – say, by unplugging it – and replace it without resetting it somehow, there will be two devices with the same ID that will both act as the same device from the hub’s and cloud’s point of view, which can have weird side effects. Sleepy devices are by default in an unresponsive state, so they can be “falsely replaced” in this way easily. If this happens, exclude both devices – the first will remove the device from the system so the second must be excluded via general device exclusion.

Also, to be clear, this is not yet the general purpose “replace” function that @brianlees suggested that can replace any SmartThings device with another that can fill the same role. It is a specific protocol-level thing that was required for Z-Wave+ certification. We’re considering expanding it to be more general though – basically to join a new device or rejoin the same one but keep all the configuration on the cloud to avoid needing to tear down all the SmartApp connections and rebuild them.

It does not seem to work at all with the Aeon MultiSensor. I have tried it on two of mine and it checks and never completes it’s process. It basically deletes the multisensor. So you’ll have to delete the smartapp if there was any associated with the device and then exclude it. Then finally include the multisensor and then add the smartapp back.

I have tried it on other devices it works fine and does what it is designed to do but so far the Aeon MultiSensor does not work.

Well, I had an issue with the Jasco light switch. I pressed the button and did the check and it recognized the device and after I verified the smartapps that I have assigned to the switch still function which they do.